changed original 500 gb HD with Seagate 1TB SSHD got flashing "?"

Went to Apple Store and they said the original HD was shot and I needed a new one. I changed the original HD with a Seagate 1T SSHD. I now get the folder with the flashing ?. It's not the cable because I can put the old drive in and the white screen with the apple opens but can't finish loading (original problem leading me to the Apple Store). This leads me to believe it may be a bad HD.

I have been backing up with a Passport. Last one was 5 days ago. When I start up computer with this attached, it doesn't see any drives to transfer the info to.

This is the first time I have ever changed a HD. Do I need to format the drive so computer can recognize? How do I do that?

2 Answers

Do you have access to a second Mac? If you do the easiest way here is to use Target Mode. Connect the two Mac's back to back via a FireWire cable then with the new drive in your system press and hold the letter T during the system startup. You should see a FireWire symbol now on your systems screen.

Now from the other system access the now visible external drive which is your systems drive. Use Disk Utility to create the GUID partition map and then create a Mac OS Extended (Journaled) partition. Once done locate on the other Mac the OS installer (you may need to access the App Store to download it run the installer App and make sure you've selected the correct drive once done you should be able to restore your stuff from your backup drive.

You got the right idea here, but, instead get a USB thumb drive (16 GB or larger) so you can prep it up from your friends Mac so it's a bootable drive, then copy to it the OS installer so you can use it as your systems boot drive. Creating one for emergency and when you need to do maintenance of your system is a smart thing!

If you have problems after doing what Dan said, replace the Hard Drive IR cable as there are known issues with these cables failing or getting damaged as they assent over the last step and the bottom case hits them.

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